If you're doing manual updates to a production DB, using START TRANSACTION and then checking the outcome of your changes before you use COMMIT stops typos becoming catastrophes.
This isn't really an issue at all but can upset those with OCD-ish tendencies.
There are arguments for and against any technique, but this one seems really ridiculous to me, especially if you consider what any "countermeasure" would do to the code (which is usually much more important than the data in the long run!).